1. Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
2. Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
3. Instituto de Ciencia Molecular, Universidad de Valencia, Catedràtico José Beltràn 2, 46980 Paterna, Spain